Method of making nuts



Feb- 19" w35- s. G. sYvERsl-:N

METHOD OF MAKING NUTS v Filed April 28, 1932 www Patented Feb. 19, 1935.

UNITED STATES PATENT OFFICE 1.992.102 v METHOD or MAKING NUTS SverreGeorgl Syversen, Nydalen, near Oslo,

Norway Application April 28, 1932, Serial No. 608,066

Germany June 4, 1931 3 Claims. (Cl. 10-86) It is formerly known tomanufacture screw nuts shown in a somewhat exaggerated degree, for inthe manner that the separate pieces of work the purposes ofillustration, in Fig. 4 and the nut are cut olf from hexagonal bars witha cross sec- Lblank or piece of work is correspondingly sometional shapecorresponding to the nuts by means what deformed. A die 9 opposite thepiston 8 has of a cutting knife, whereupon such pieces by a recess 10adapted to shape the inclined nut 5 means of the said knife are passedon to a punchedges on one side during the punching operation. ing dieand are then punchedor perforated. In The knife 1 is withdrawn duringthe perforacarrying out this method the pieces are treated tion of thepiece of work by the piston 8, the in a heated condition. l fingers 3sliding over the piece. When the knife 10 The present invention relatesto a device for 1 and the piston 8 have been withdrawn, the 10 themanufacture of screw nuts in a cold condipiece of work falls down to thebottom 11 of tion. The expenses connected with the heat the channel '7.Then a draw-piston 12 enters in treatment are thereby avoided as well asthe operation and forces the piece of work through alterations in thequalities of the piece caused a draw-die 13 provided with a widenedmouth 15 by such treatment. Further, the invention makes 14. During thisstep the piece is calibrated, the 15 use of finishing the nuts bypushing them through material being compressed from outside, whereadraw-die as commonly used in the manufacture by the exterior sides ofthe nut are reshaped and of nuts when cutting them from a flat bar orreturned to their original form exactly parallel to stamping them fromplates or the like. and atA the correct distance from the axis as willThis is obtained according to the invention by be understood. Furthersome material is dis- 20 the arrangement that the cutting knife operatesplaced on to the central nut portion, whereby the perpendicularly to avertical channel, in the tapered hole is transformed into a cylindricalupper part of which a punching piston operates shape, and the hole isnow well adapted to receive transversely to the channel, whereas thepiece the threads produced in the ordinary way. of work is stillretained by the cutting knife, then I am aware that nuts have beenheretofore 25 firstly the knife and secondly the punching piston madefrom hexagonal bars. However, the blanks are withdrawn and the punchedor perforated have according to the known methods been compiece fallsthrough the channel in front of a drawpressed by pressure endwise eitherin a mould or die and is then pushed through same. freely, so that theouterl surface is bowed. In An embodiment of the invention isillustrated in the rst case punching of the hole has taken place 30 theaccompanyingdrawing. Fig. 1 is an elevawhen the blank was placed in themould, .and tion of the device. Fig. 2 is a longitudinal secin thelatter case a Calibrating operation of the tional view on the lineII-II, Fig. 1. Fig. 3 is a outer surface was made. In both cases thefinal cross sectional view on the line III-III of Fig. 1. form of thehole will, owing to the elasticity or Fig. 4 is an enlarged detailsectional view of the ductility of the cold material, be notcylindrical. 35 nut blank after being punched, and disclosing theAccording to my invention the hole will be cylintapered bore formed bythe punching operation. drical when the Calibrating operation of the Inthe drawing 1 denotes the cutting knife servouter surface takes placeafter removal of the ing to cut off a piece of work from a hexagonalpunch from the hole.

bar 2. Spring fingers 3 with bent ends are I claim: 40 adapted to retainthe cut piece of work in posi- 1. The method of making a nut, consistingin tion in relation to the cutting knife. forcing out the centralportion of a blank through The hexagonal bar 2 is fed through guides 4,5, a die by means of a punch while the side faces and the correct heightof the piece of work is seof the blank are unconned and thereby formingcured by means of an abutment l6. By the knife a bore through the blank,and thereafter forcing 45 1 and the ngers 3 the piece of work is thensuch bored blank through a draw'die by means passed into a verticalchannel '7 and is retained of a draw piston to thereby correctdeformations therein provisionally by the knife 1 and the fingers of theside faces and also impart true cylindrical 3 until a punching piston 8has been forced form to the bor'e.

through the piece to produce the thread bore in 2. The method of makinga nut, consisting in 50 same. During the punching of the bore by thelforcing out the central portion of a cold blank piston lateral radialstresses are set up which inthrough a die by means of a punch while theside crease progressively so that although the punchfaces of the blankare unconfined and thereby ing piston is of true cylindrical form, thebore forming a bore through the blank, and thereafter formed thereby isof slightly tapered form as forcing such bored blank while cold throughu 55 i l g 10 means oi. said punchwhile the side faces of the blank areunconfined and thereby forming a bore through the blank, releasing thebored blank from the knife and from between said die and said punch andthereafter forcing such bored blank through a draw die by,means of adraw piston to thereby correct deformations of the side faces of theblank and also impart true cylindrical form to the bore thereof.

SV'ERRE GEORG SYVERSEN.

